• WordNet 3.6
    • v leaven cause to puff up with a leaven "unleavened bread"
    • n leaven an influence that works subtly to lighten or modify something "his sermons benefited from a leavening of humor"
    • n leaven a substance used to produce fermentation in dough or a liquid
    • ***
Webster's Revised Unabridged Dictionary
    • Leaven Any substance that produces, or is designed to produce, fermentation, as in dough or liquids; esp., a portion of fermenting dough, which, mixed with a larger quantity of dough, produces a general change in the mass, and renders it light; yeast; barm.
    • Leaven Anything which makes a general assimilating (especially a corrupting) change in the mass. "Beware of the leaven of the Pharisees, which is hypocrisy."
    • Leaven To imbue; to infect; to vitiate. "With these and the like deceivable doctrines, he leavens also his prayer."
    • Leaven To make light by the action of leaven; to cause to ferment. "A little leaven leaveneth the whole lump."
    • ***
Century Dictionary and Cyclopedia
    • n leaven See leven.
    • n leaven A substance that produces or is designed to produce fermentation, especially in dough; specifically, a mass of fermenting dough, which, mixed with a larger quantity of dough or paste, produces fermentation in it and renders it light.
    • n leaven Something that resembles leaven in its effects, as some secret or impalpable influence working a general change, especially a change for the worse.
    • leaven To excite fermentation in; raise and make light, as dough or paste.
    • leaven To imbue; work upon by some invisible or powerful influence.
    • leaven To ripen; mature.
    • ***
Chambers's Twentieth Century Dictionary
    • n Leaven lev′n the ferment which makes dough rise in a spongy form: anything that makes a general change, whether good or bad
    • v.t Leaven to raise with leaven: to taint
    • ***


  • William Mcilvanney
    William Mcilvanney
    “Good lies need a leavening of truth to make them palatable.”
  • George F. Will
    “If your job is to leaven ordinary lives with elevating spectacle, be elevating or be gone.”


Webster's Revised Unabridged Dictionary
OE. levain, levein, F. levain, L. levamen, alleviation, mitigation; but taken in the sense of, a raising, that which raises, fr. levare, to raise. See Lever (n.)


In literature:

These grains of leaven will actually leaven the whole lump.
"Twentieth Century Negro Literature" by Various
The lump had invited the leaven.
"A Dream of Empire" by William Henry Venable
The question is legitimate: Have we nothing to fear from the leaven of political fragmentarism in Europe?
"Continental Monthly , Vol V. Issue III. March, 1864" by Various
I am very tired of Caleb's continued company; that is, with nothing to leaven it.
"Then I'll Come Back to You" by Larry Evans
Far from us, monsieur, those old leavens of feudal abuses!
"The Vicomte de Bragelonne" by Alexandre Dumas
But now, new thoughts were stirring within her, were leavening her whole mind.
"The Danvers Jewels, and Sir Charles Danvers" by Mary Cholmondeley
The real reason why all southern Europe is in a turmoil to-day, is that American ideas of liberty are working there like leaven.
"Aliens or Americans?" by Howard B. Grose
The ceremonial of the preparation of the bread (which is leavened and in the form of a small loaf) is exceedingly complex.
"Russia" by Various
Nature is the baker, the loaf is the body, the leaven is the germ-plasm, and each baking is a generation.
"Applied Eugenics" by Paul Popenoe and Roswell Hill Johnson
Christianity itself was not of Rome, it was an eastern leaven in Roman society.
"Encyclopaedia Britannica, 11th Edition, Volume 4, Part 4" by Various

In poetry:

Far better than the love we win,
That earthly passions leaven,
Is love we lose, that knows no sin,
That points the path to Heaven.
"Love And Loss" by Madison Julius Cawein
To sit ... till every sense
Lose thought of whither and whence;
Till earth and heaven
And faith and fate
No longer leaven
Life, with hope or fear, or love or hate.
"By A Silent Stream" by Cale Young Rice
But if there lives, as love believes,
All underneath this silent heaven,
In yon shades, and by yon streams,
As we have seen them in our dreams,
A deathless race; still let thy grace
My being leaven!
"To Poesy" by Charles Harpur
How much the uncharitable leaven
Is mingled with our daily fare!
How little do we think of heaven
When earth absorbs us everywhere!
We see our neighbour's fault and sin,
But quite forget to look within.
"Introspection" by John Bowring
So much for the culprit. Who's the martyred man?
Let him bear one stroke more, for be sure he can!
He that strove thus evil's lump with good to leaven,
Let him give his blood at last and get his heaven!
"Before" by Robert Browning
When with swift, unsandall'd feet,
Thou the springing turf dost tread,
In the passion of the chase,
Long'st thou for the leavened bread?
Wouldst thou sleep the scented night
Where the stars are hid from sight?
"Ishmael" by Ethel Clifford

In news:

Potomac Media Works develops, writes and produces entertaining television programming exploring contemporary and global topics — often leavened with a gently irreverent tone.
Two men performing the pre-Passover ritual of burning leavened bread were given a summons by fire marshals because the fire, on a Brooklyn street, created a danger, the Fire Department said yesterday.
In Israel the Passover restrictions that rule out leavened bread and wheat apply to livestock as well so that their milk can be considered kosher for Passover.
An app to get rid of your leavened bread.
The jungle quest that results, while redolent of Heart of Darkness and Don Quixote, takes readers to a place entirely Millet 's own, leavened by very funny asides.
To see the December protests in Russia as primarily a political wave is to miss a more fundamental leaven at work in Russian society: a moral awakening akin to the American civil rights movement .
Words of experience leavened by practical advice.
Let's get it out of the way up top that I think The Huffington Post is a mess—a schizophrenic, mostly unreadable hunk of tabloid journalism leavened with serious stuff.
At their base, pancakes and waffles depend on a few key ingredients: flour, salt, sugar and leavener.
Ultra-Orthodox Jewish men burn leavened items in a final preparation before the Passover .
In Israel the Passover restrictions that rule out leavened bread and wheat apply to livestock as well so that their milk can be considered kosher for Passover .
Critics embraced 2006's I Am Not Afraid of You and I Will Beat Your Ass because it leavened the Hoboken, New Jersey trio's sprawling guitar orgies with the band's sprightliest tempos in ages.
In typical Dutch fashion, the avant-garde here is leavened with a playful wit.
M atzoh, the flatbread traditionally eaten at the Passover Seder , is made with not the most exciting ingredients—white flour, water, salt (and no leavening).
A weekly, hour-long romp through the worlds of media, politics, sports and show business, leavened with an eclectic mix of mysterious music, hosted by Harry Shearer .

In science:

Sempre nell’ambito dei tempi complessi, Leavens e Aers, nel 1993, partendo dallo stesso operatore introdotto da Sokolovski e Baskin (τ Ω cl ), propongono l’uso del metodo di Bohm per ricavare delle traiettorie “semiclassiche” da adoperare per il calcolo del tempo medio.
Tempi di Tunnelling (Tunneling Times)
Leavens, G.T., et al., JML Reference Manual. 2005. Lange, C.F.J., M.R.V. Chaudron, and J. Muskens, In practice: UML software architecture and design description. Software, IEEE, 2006. 23(2): p.
Test Case Generation using Mutation Operators and Fault Classification
This fact has already been pointed out by Leavens , but he makes no comment on the imaginary part.
Weak Values: Approach through the Clifford and Moyal Algebras
Leavens, C. R., Weak Measurements from the Point of View of Bohmian Mechanics, Found.
Weak Values: Approach through the Clifford and Moyal Algebras